Using data from five cycles of the Canadian Community Health Survey spanning 2005 to 2014, we assessed changes in household food insecurity in Ontario after the 2007 introduction of the Ontario Child Benefit and the 2008 implementation of the province’s poverty reduction strategy. Although the provincial prevalence of food insecurity remained relatively stable, food insecurity declined significantly among families who received the Ontario Child Benefit in 2009–2010 and 2011–2012 compared with 2005. Our findings suggest that household food insecurity can be reduced by modest income supplements, but more deliberate intervention is required to have a substantial, sustained impact on food insecurity.